The thesis statement of an essay identifies what the essay is about and why the subject of the essay is being discussed--its significance, importance, relevance, or value (SIRV). While the thesis usually comes at the end of the first paragraph of an essay, it may appear elsewhere in the essay. Sometimes students will begin an essay with just a thesis statement. The problem in doing this is that the thesis statement usually requires some background information be presented to help the reader understand the thesis. Some instructors may require students to underline the thesis statements in their essays, but the thesis statement should be easily recognizable by its role in stating the main idea of the essay, whether or not it is underlined.

In most cases, the topic of an essay is the subject of the thesis sentence and the focus on that topic is clarified by the verb and complement of the thesis sentence. The verb and its complement typically explain the significance, importance, relevance, or value (SIRV) of the topic under discussion. In addition, the thesis will logically appear at the end of the introduction. Students who bury the thesis statement somewhere else in the essay often create papers that do not seem to have a thesis or which seem to have conflicting thesis statements.

Sometimes an essay may have an implied thesis where the purpose of the essay is so clear that it does not need to be stated. However, implied thesis statements are rarely used in argument essays. Most college composition teachers do not want students to use the implied thesis. An exception occurs in satire, where the thesis is implied by the ridicule of its opposite, the stated thesis of the essay. So, the implied thesis statement is an ironic criticism of the supposed--and expressed--thesis.

For instance, the thesis of Jonathan Swift's "A Modest Proposal for Preventing the Children of Poor People in Ireland from Being a Burden to Their Parents or Country,. and for Making Them Beneficial to the Public" is that poor parents should raise as many children as possible and sell them for food. Swift isn't actually calling for parents to raise their children for food. Instead, his satirical treatment of the subject criticises the flawed and uncaring attitude of his society toward Ireland's poor.

Format of a Thesis Statement

The subject of the thesis statement must be the agent that should perform the action being argued.

The verb of the thesis statement for an argument essay should be a strong, and specific action verb, generally preceded by should (should not) or must (must not). Avoid the use of the verbs "is" or "are."

The remainder of the sentence should either be an argument for why action needs to be taken or the specific action or re-orientation of thinking necessary to achieve a specific goal.

Argument essays seek either a change in behavior or a re-orientation in thinking. Some argument essays offer reasons or evidence in favor of one option among several. Some argument essays debate options, offering pros and cons for each in an effort to show that one option is superior to the others. Other argument essays use gathered evidence to persuade the reader to adopt a point of view or pattern of behavior contrary to the reader's normal thinking or behavior. Others present and evaluate evidence in order to reach what appears to be the best or most reasonable conclusion. Still others attempt to persuade by consensus, acknowledging the strengths of one point of view or pattern of behavior and then providing evidence to suggest that another point of view or pattern of behavior more successfully addresses the situation.

Examples of Thesis Statements

NASA should not focus its efforts on manned space flight because it is less efficient than unmanned flights, the risk to humans is too great, and the costs cannot be justified.

The President of the United States must reconstitute the draft in order to supply troops in foreign arenas to achieve American goals of security and peace.

More students should be encouraged to explore career paths in the technical fields to meet the demands of contemporary work.

STEAM programs should include significant courses from the arts and humanities to provide students with the broader context, implications, and ethical concerns that STEAM has for society and contemporary life.

The U.S. Government should remove Environmental Protection Agency regulations that limit the expansion and profit margins of American companies.

The U.S. Government should continue to enforce and expand Enviromental Protection Agency regulations to ensure that American companies do not allow profit margins to replace concerns for human and environmental safety.

Students should learn about other cultural influences affecting all Americans rather than focusing on those influences specific to their own particular backgrounds, ethnicities, or national origins.